Quote Originally Posted by emily_in_nc View Post
Good information, Catrin, thanks. I knew that planks were isometric but couldn't think of too many other examples. It's definitely easier to do them on an angle against a wall. On the floor is hard as it uses a lot of core strength; it's certainly not just an upper body exercise. A side plank uses a lot of upper body but would probably be too tough on your shoulders.
Yes, no way I can do a side plank. There are many other ways as well - holding a weight in a static position without moving for a period of time, hard to explain but I think you understand. The important thing is the joint doesn't move and the muscle doesn't lengthen - and while some do use weights - body weight is usually enough. I've got to be more careful than many but I won't give up!